Metadata is information associated with material such as video and audio. Some types of metadata describe the form of encoding of e.g. a compressed video signal to assist in the decoding thereof. Other types of metadata describe the content of the video. For example such descriptive metadata may include the title of the video and other information such as when and where the video was shot. Yet other types of metadata are technical information such as aspect ratio, lens used, video format etc. Yet further types include information such as Good Shot Markers, copyright information, and information about people appearing in the video. Many other types of data may be metadata.
A prior proposal suggested that metadata is stored separately from the material with which it is associated. The metadata may be stored in a data base and some means of linking it with the material is provided. Such means could be e.g. a code on a video-cassette. If the link is lost then the metadata cannot be associated with the material. If the database is destroyed then the metadata is lost. Thus it is desirable to combine at least some metadata with the material.
It is necessary to store material in a store such as a digital video tape recorder (DVTR) or a digital disc recorder. It is also desirable to repeat metadata so that it can be accessed more easily in e.g. a tape record without needing to spool back to the beginning of the tape. However most DVTRs and disc recorders have a data format which does not provide data space dedicated to metadata repeated at regular intervals in the digital bitstream.